The present invention relates generally to multiple load path connectors for fail-safe structural or load carrying mechanical joints and more particularly to a novel pinned clevis or double lug pair connection wherein two separate load bearing paths are provided to carry a load in a fail-safe manner, one path carrying the load upon failure of the other.
Prior attempts to provide multiple load path joint connectors have included use of a pin-within-a-pin arrangement and dual clevis or lugs. Also, large diameter pins have been used to provide a low stress level and extended safe life design. These solutions may ordinarily be suitable when sifficient space exists for their installation. However, the use of large diameter pins requires large lug or clevis dimensions, and, if bolt clamp-up is desired for preloads in reducing bolt bending stresses, large size bolt heads and nuts are also required. For certain applications, such as in the mechanical linkages for movable airfoils on aircraft, unlimited working space and weight allowance are not available. Multiple load path connections may nevertheless be required for safe life aircraft design for redundant structural or mechanical connections in areas where a single failure may result in loss of the aircraft.
The present invention provides a novel single pin structural or mechanical joint including a primary and a standby load path across the joint. The pivotal connector configuration disclosed herein may be applicable to simple pin joints or to self-aligning joints requiring rotational alignment about axes other than the pin axis. The invention provides a mechanical joint which may include both safe life and dual load path characteristics and which may be inspected for component failure without disassembling the joint. Further, the present invention avoids space availability problems characteristic of existing structures wherein space for self-aligning joints in a diametrical direction may be limited, which may be characteristic of certain existing thin wing fighter aircraft, by using slightly increased amount of space in an axial direction which is often available.
It is, therefore, a principal object of the present invention to provide an improved multiple load path connector.
It is a further object of the invention to provide a dual load path, fail safe, single pin connector for structural or mechanical joints.
It is a further object to provide a self-aligning dual load path pivotal connector for control linkage or support for movable airfoils on aircraft.
These and other objects of the present invention will become apparent as the detailed description of certain representative embodiments thereof proceeds.